Sonic polishing apparatus

ABSTRACT

A resonant finishing apparatus having a finishing chamber is provided with means for recirculating parts and/or finishing medium between spaced portions of said chamber in response to resonant vibration of said chamber.

United States Patent Inventor Howard E. McKinney Lo 1011:, Calif. App]. No. 770,223 Filed Oct. 24, 1968 Patented Aug. 3, 1971 Assignee Shell 011 Company New York, N.Y. Continuation-impart 01 application Ser. No. 710,993, Mar. 6, 1968.

SONIC POLISHING APPARATUS 5 Claims, 5 Drawing Figs.

US. Cl 51/7, 5 l/ 163 Int. Cl. .3245 19/00, B24b 31/00 FieldotSeorch 51/7. 163

[56] References Cited UNITED STATES PATENTS $496,677 2/ 1970 Bodine 511163 X 3,290,836 12/1966 Ruppe 51/7 x 2,722,840 11/1955 Kececiog1u.... 51/7 UX 2,967,434 1/1961 Mahlfeldt... 51/7 UX 2,757,544 8/1956 Becker 51/7 UX FOREIGN PATENTS 141,404 1960 U.S.S.R. 51/7 768,888 2/1957 Great Britain 51/7 Primary Examiner-Harold D. Whitehead Attorneys-Freling E. Baker and J. H. McCarthy ABSTRACT: A resonant finishing apparatus having a finishing chamber is provided with'means for recirculating parts and/or finishing medium between spaced portions of said chamber in response to resonant vibration of said chamber.

OSCILLATOR FIG. 2

INVENTORI HOWARD E. Mc KINNEY 2% 8 film HIS ATTORNEY PATENTEU Am; 3 l9?! SHEET 2 BF 2 FIG. 3

FIG. 4-

SONIC POLISHING APPARATUS CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of my copending application, Ser. No. 7 l0,993,filed Mar. 6, 1968.

BACKGROUND OF THE INVENTION The present invention relates to the art of sonic finishing of industrial parts and pertains more particularly to a continuous flow process of sonic finishing of industrial parts.

Industrial parts are fabricated by any number of means or methods including casting, forging and machining. Parts emerging from any of these fabrication steps normally are rough, contain burrs and sharp edges and in the case of castings contain molding sand imbedded in the surface thereof. These parts normally need finishing such as cleaning, deburring, edges rounded and polishing prior to further machining or assembly into machines. Many techniques have been used for cleaning and polishing or finishing of these parts including handscrubbing and grinding. Other methods of cleaning and finishing of these parts include tumbling and shaking of the parts in a grit medium. The tumbling-type finishing operation is carried out by loading the parts in a barrel or bin-type container which is partially filled with a grit medium and then tumbling the parts in the grit medium by rotating the containerabout a horizontal axis. The shakingtype finishing apparatus bodily shakes or generally employs eccentric mass-type shakers or vibrators to vibrate a container containing suitable finishing medium andparts. This type of vibration requires massive shakers or vibrators to develop the necessary forces involved in large batch-type containers. The above-described methods of cleaning and finishing are time consuming and cannot keep up with modern techniques for the production of industrial parts.

The present invention employsthe principle of a resonantly vibrating sonic system for the introduction of high levels of sonic energy rapidly and efiiciently into a cleaning or finishing medium. The elastic resonant sonic vibration system of the present invention permits the use of a steady flow process of parts finishing wherein the parts go through the finishing chamber at such a rate as to obtain the desired finishing in a short period of time.

The energy-transmitting system of the present invention employs a resonantly vibratingsystem which may be referred to as an acoustic circuit. For a better understanding of such systems, a close analogy may be drawn between the acoustic circuit and an electrical circuit as pointed out, for example, in chapter 2 of Sonics by Heuter and Bolt, published in 1955 by John Wiley and Sons.

The present invention overcomes the foregoing problems in the prior art devices and methods by providing a method and apparatus for a continuous flow process for sonic cleaning of industrial parts. The present system comprises a resonantly vibrating polishing chamber through which the parts pass in intimate contact with the polishing or finishing medium.

BRIEF DESCRIPTION OF THE DRAWINGS Many additional objects and advantages of the present invention will be evident to those skilled in the art from the following detail description and drawings wherein:

FIG. 1 is a schematic illustration of a suitable layout for a system in accordance with the present invention;

FIG. 2 is a side elevation partially in section of a preferred embodiment of apparatus for carrying out the present invention;

FIG. 3 is a side elevation in section of a second embodiment of the present invention;

FIG. 4 is a side elevation in section of a third embodiment of the present invention;

FIG. 5 is a view in section of a fourth embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With particular reference to FIG. I there is illustrated a schematic layout of a suitable system for carrying out the present invention. As shown in FIG. I, there is illustrated a conduit member 11 which is preferably constructed of a suitable elastic material, and forms a polishing chamber l2 through which articles to be polished are passed in the cleaning process. The conduit member may be of any suitable cross section and may even be an open channel or trough. A sonic oscillator 13 is operatively coupled to the conduit member 11 to transmit elastic vibrations into a polishing medium contained in its chamber 12. The oscillator 13 and elastic conduit member 11 form an elastic sonic energy transmission system which when operated at or near its resonance frequency provides for the rapid and efficient delivery of energy to the polishing medium in the chamber. Parts 10a, 10b and to be polished pass, such as along a path 14, into chamber 12 wherein the polishing medium under the influence of sonic energy impacts against and along the surfaces of the parts providing effective cleaning and polishing thereof. The polishing medium, which may be any suitable type of abrasive particles such as an aluminum oxide, may be retained in a chamber 12 as the articles are passed therethrough or in the alternative may be arranged so as to flow therethrough substantially along with the articles. Moreover, provisions may be made for the recycling of the abrasive or polishing medium such as along the path such as 15. The polishing media may be of any suitable type or composition to obtain the desired results. For example, the medium may comprise dry granules or may be slightly moistened as desired. Also, the medium may be a slurry comprising abrasive particles suspended in a suitable liquid. The level of polishing medium in chamber 12 and the rate of flow therethrough of the medium as. well as the articles to be polished is preferably adjustable all independently in order to obtain the proper degree of finishing.

In FIG. 2 is illustrated a suitable arrangement of apparatus of carrying out the present invention. As shown in FIG. 2 an elastic conduit member 18 forms a polishing chamber 19 and serves to transmit energy from a sonic vibration generator 20 into the polishing medium 16. The oscillator 20 is coupled such as by means of a band or clamp 21 to the conduit member l8. The vibration generator 20 is preferably though not limited to the orbiting mass-type oscillator, such as disclosed in U.S. Pat. No. 2,960.3]4, issued to A. G. Bodine on Nov. 15, I960. The oscillator may be of the single roller type or twin roller type. With a single roller type with its rotative axis parallel to axis of the elastic member 18 will undergo a gyrating elastic standing wave motion characteristic of an elastic standing wave pattern with the ends and center of the tube undergoing a gyratory motion. A latteral standing mode of vibration may be obtained by the use of a dual roller oscillator having counterrotating rollers or by the use of a single roller oscillator having its rotative axis perpendicular to the conduit member 18. Suitable means such as a hopper orchute 22 is utilized for feeding or conveying the polishing medium 16 and parts 17a, 17b, and 17c to the polishing chamber 19. The hopper 22 is preferably vibrationally isolated from conduit member 18 such as by means of a resilient or elastomeric ring 23 held in place such as by expandable metal bands 24 and 25.

At least some portion of the flow path of the present invention is preferably tilted to provide a continuous gravity feed of the materials through the polishing chamber. Of course, other methods of inducing flow, such as pumping may be utilized to maintain a suitable rate of flow through the polishing chamber. The apparatus illustrated. in FIG. 2 is supported from suitable support means such as the base member 26 from which extends a vertical strut member 27. The elastic conduit member 18 is preferably supported at nodal points by suitable vibration-isolating means such as an elastomeric band 28 surrounded by band member 29 which is in turn pivotally supported by pine 30 to strut 27. A second elastomeric band 33 and metal band 34 encircle the elastic conduit 18 in the vicinity of the upper nodal point and is in turn pivotally connected by pivot pin 35 to an extendible support member such as fluid transducer 36 which is in turn pivotally supported by pivot pin 38 to base member 26. A conduit 39 extends to a suitable source (not shown) of hydraulic fluid for operating the fluid motor 36. The above-described support structure permits the adjustment of the tilt of the conduit 18 and consequently the rate of flow as well as the volume of material in a chamber 19 at a given moment. The rate of flow will determine the residence time or length of time spent in the chamber by the part. A high degree of filling of the polishing chamber 19 with polishing medium provides a better sonic coupling of the energy from the conduit 18 into the polishing medium in chamber 19 and consequently an increased rate of finishing and polishing of the parts fed therethrough. A suitable bin 45 is located at the discharge end of conduit 18 to catch the polishing medium upon its discharge from the polishing chamber. The parts may be permitted to fall in a heap with the polishing medium from which'it is there retrieved or they may be preferably caught by means of a conveyor belt or chain 46 which permits an unrestricted flow of the polishing medium therethrough into the bin 45. The conveyor 46 is supported such as by means of roller 47 and driven by suitable means not shown. Suitable guide panels 48 and 49 supportedby means of a strut 50 extend along the sides of tee conveyor belt or chain 46.

Referring now to FIG. 3, there is illustrated a further embodiment of the present invention comprising an elastic tubular housing member 53 having barrier means 54 and 55 positioned therein and forming a finishing chamber 56 for containing a suitable finishing medium 57, recirculating means 58 in the form of a conduit provides means for recirculating the finishing medium or finishing medium and parts being finished therein. Recirculation conduit 58 preferably communicates with the interior chamber 56 at or near nodal points or areas of housing member 53. Nodal areas are areas of minimum vibration in the housing member when under the influence of resonant vibration. Other suitable areas of communication may be desirable, such as for example nodal to antinodal areas. A suitable opening or port 59 in the recirculating conduit means 58 permits the introduction of finishing medium or parts into the system. A second opening or port 65 may be provided for the removal of parts and medium from conduit 58. A suitable sonic oscillator 60 is operatively coupled to housing means 53 to generate resonant vibrations therein. The sonic oscillator or vibration generator 60 is preferably of a single-orbiting rotor type mounted such that its axis is substantially parallel to the axis of housing number 53 such that gyratory vibrations are generated within housing number 53. This system has been found to be effective in response to gyratory vibrations in the housing 53 from a suitable sonic oscillator to cause a continuous flow of medium through chamber 56 and around through recirculating conduit 58 as indicated by arrow 61. A slight tilting of housing 53 is sometimes necessary to initiate the flow of the medium through the circuit. Once the flow has started, however, the housing member 53 may be brought back to the level position while the medium will continue to flow through the recirculating circuit. The illustrated embodiment may be suitable for the surface finishing of elongated members, such as a pipe or rod or any other elongated element 62. Suitable ports or openings 63 and 64 are provided in barrier or wall means 54 and 55 so that an element 62 may be passed therethrough. This embodiment may be also suitable for the cleaning of small articles of manufacture which may be inserted into the system at any suitable place such as a port 59 and removed therefrom after suitable passage through finishing chamber 56. The recirculating conduit 58 also provides an effective means for adjusting the pressure within chamber 56. This adjustment is carried out by adjusting the height of conduit member 58 above the chamber 56. Thus, the pressure within the chamber 56 may be adjusted to obtain the optimum finishing rates by adjusting the height of recirculating conduit 58 above said chamber. The conduit 58 is preferably constructed of a resilient material such as rubber or neoprene.

Referring now to FIG. 4, there is illustrated a further embodiment of the present invention in which an elastic tubular housing member 67 is provided with suitable barrier or wall means 68 and 69 forming a finishing chamber 70 therein for containing a finishing medium 71. The barriers or wall means 68 and 69 may be of any suitable material and need not be rubber or neoprene as in the FIG. 3 embodiment, since no elements are to pass therethrough. A suitable recirculating conduit 72 communicates by means of ports 73 and 74 between portions of chamber 70. These ports or openings 73 and 74 are preferably at or near nodal areas in housing member 67 when under the influence of resonant vibrations. The recirculating conduit 72 is preferably provided with lands, which may be helical or circumferential, within a portion of the inner wall thereof to improve the recirculation of parts of medium therethrough. A first port or opening 76 may be provided in conduit means 72 for introducing parts or medium therein and a second port or opening 77 may be provided for the removal of parts therefrom. The recirculating conduit is preferably constructed of a flexible material. A suitable sonic oscillator or vibration generator is operatively coupled to a housing member 67 for generating resonant vibrations therein.

Referring now to FIG. 5, there is illustrated a further embodiment of the present invention in which an elastic tubular housing member 78 is provided with suitable barrier or wall means 79 and 80 to close off and form a chamber 81 within the bore thereof. Inertia means which may be in the form of annular masses 82 and 83 are suitably attached or coupled to the ends of housing 78 to move the nodal areas of said housing 78 closer to the ends thereof. This permits the barriers or wall means 79 and 80 to be moved outward to the nodal areas so that a larger chamber maybe obtained than ordinarily from a given length of housing 78. A suitable sonic oscillator or vibration generator 84 is operatively coupled to housing 78 to set up resonant gyratory vibrations therein. Suitable ports or openings 85 and 86 are provided in the walls of housing 78 for the introduction and/or removal of either parts or medium into or removal from chamber 81. With such systems as illustrated under the influence of gyratory vibrations, parts or workpieces immediately migrate to the nodal areas, whereas the medium migrates to the antinodal areas. Since the antinodal areas are the areas of maximum vibrational amplitude and high-cutting rate, it is desirable that the workparts pass through this area. Thus, the workpiece may be ideally introduced into chamber 81 at an antinodal area 86 and removed at a nodal area, such as 85. Whereas the medium may be introduced into the system at a nodal area such as 85 and removed therefrom at the antinodal area 86. Thus, the above system is also an automatic separator of media and parts. Also ports or openings 85 and 86 may be connected together by means of a suitable recirculating conduit if desired.

While the invention has been described in detail with respect to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims.

lclaim:

l. A continuous flow surface finishing apparatus, said apparatus comprising:

an elastic tubular member;

an oscillator operatively coupled to said tubular member for generating gyratory elastic resonant vibrations therein; barrier means positioned in the bore of said tubular member and forming a chamber therein;

means for introducing a finished medium into said chamber;

means for introducing elements to be finished into said chamber; and

means responsive to said gyratory vibrations for recirculating said finishing medium.

conduit means for introducing finishing medium and elements to be cleaned therein.

5. The apparatus of claim l comprising openings in said barrier means to permit the passing of elongated elements through said chamber. 

1. A continuous flow surface finishing apparatus, said apparatus comprising: an elastic tubular member; an oscillator operatively coupled to said tubular member for generating gyratory elastic resonant vibrations therein; barrier means positioned in the bore of said tubular member and forming a chamber therein; means for introducing a finished medium into said chamber; means for introducing elements to be finished into said chamber; and means responsive to said gyratory vibrations for recirculating said finishing medium.
 2. The apparatus of claim 1 wherein said recirculating means comprises conduit means communicating between two areas of said finishing chamber.
 3. The apparatus of claim 2 wherein said points are adjacent to the nodes of said tubular member.
 4. The apparatus of claim 2 comprising openings in said conduit means for introducing finishing medium and elements to be cleaned therein.
 5. The apparatus of claim 1 comprising openings in said barrier means to permit the passing of elongated elements through said chamber. 